With the NR class now going through a re-power programme,where the GE 7FDL-16 prime mover is being replaced. With NR 23 the first locomotive through, the only visible change is LED replacements in the head and marker lights, plus inline refueling equipment.
Looking back, National Rail published the following livery diagrams on their website many years ago.
For a fine description of weathering a Austrains NR model, go to the Barcoola blog site.
Plus modified livery drawing for early PN livery.